• Transactions of the Korean hydrogen and new energy society
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• v.22 no.4
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• pp.458-464
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• 2011

Recently, one of the hydrogen production methods has attracted using dense metallic membrane. It has high hydrogen permeation and selectivity which hardly could adopt industrial product because of high cost, hydrogen embrittlment and thermal stability. Meanwhile, vanadium has high hydrogen solubility and it use to instead of Pd-Ag amorphous membrane. Aluminum carried out blocking hydrogen diffusion on grain boundary therefore protecting hydrogen embrittlement. Most of dense metallic membrane is solution diffusion mechanism. The solution diffusion mechanism was very similar hydrogen storing steps such as steps of metal hydride. Thus, V-Al composites were fabricated to use hydrogen induced mechanical alloying. The fabricated V-Al composites were characterized by XRD, SEM, EDS and simultaneous TG/DSC analyses. The hydrogenation behaviors were evaluated using a Sievert's type automatic PCT apparatus. The hydrogenation behaviors of V-Al composites was evaluated too low hydrogen stored capacity and fast hydrogenation kinetics. In PCI results, V-Al composites had low hydrogen solubility, in spite of that, hydrogen kinetics was calculated very fast and hydrogen absorption/desorption contents were same capacity.

• Journal of Pharmaceutical Investigation
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• v.26 no.3
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• pp.215-219
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• 1996

Active component was sought among three herb medicines, which are used in combination as a traditional medicine prescribed for patients with hyperlipidemia related diseases. Antihyperlipidemic effect of this remedy has previously been shown model by the authors on the animal model. Hyperlipidemia was induced on male Wistar rats by keeping them on high lipid diet for one week, as previously described by the authors. Blood lipid profile was verified on these rats by measuring total cholesterol (TC), triglyceride (TG), high density lipoprotein (HDL) and low density lipoprotein (LDL). Then, the diet was changed to normal. At the same time, methanol extracts of Scutellaris baicalensis Georg.(radix), Coptidis japonica Makino(rhizoma) or Rhei koreanum Nakai(rhizoma) were given on daily basis, and changes in the blood lipid profile were monitored for 4 weeks. Methanol extract of Scutellaris baicalensis Georg. significantly reduced the TC value, implying the in vivo antihyperlipidemic effect.

• Journal of the Korean Ceramic Society
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• v.49 no.6
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• pp.523-527
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• 2012

Silicon carbide (SiC) has recently drawn an enormous amount of industrial interest due to its useful mechanical properties, such as its thermal resistance, abrasion resistance and thermal conductivity at high temperatures. In this study, RF thermal plasma (PL-35 Induction Plasma, Tekna CO., Canada) was utilized for the synthesis of high-purity SiC powder from an organic precursor (hexamethyldisilazane, vinyltrimethoxysilane). It was found that the SiC powders obtained by the RF thermal plasma treatment included free carbon and amorphous silica ($SiO_2$). The SiC powders were further purified by a thermal treatment and a HF treatment, resulting in high-purity SiC nano-powder. The particle diameter of the synthesized SiC powder was less than 30 nm. Detailed properties of the microstructure, phase composition, and free carbon content were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), a thermogravimetric (TG) analysis, according to the and Brunauer-Emmett-Teller (BET) specific surface area from N2 isotherms at 77 K.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.11a
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• pp.133-134
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• 2021

Limestone-calcined clay-Cement (LC3) concrete provides a solution for sustainability, durability, and profitability of concrete industry. This study shows experimental studies of the macro properties (residual compressive strength), the meso properties (mesoscopic images), and micro properties (thermogravimetric (TG) analysis, X-ray powder diffraction (XRD), FTIR spectra, Raman spectra, Mercury intrusion porosimetry, and SEM) of LC3 paste with various mixtures and at high elevated temperatures (20 ℃, 300 ℃, 550 ℃ and 900 ℃). We find (1) Regarding to macro properties, LC3 cementitious materials are at a disadvantage in compressive strength when the temperature is higher than 300 ℃. (2) Regarding to meso properties, when the temperature reached 550 ℃, all samples generated more meso cracks. (3) Regarding to micro properties, first, as the substitution amount increases, its CH content decreases significantly; second, at 900 ℃, for samples with calcined clay, a large amount of gehlenite crystalline phase was found; third, at elevated temperatures (20 ℃, 300 ℃, 550 ℃ and 900 ℃), there is a linear relationship between the residual compressive strength and the cumulative pore volume; fourth, at 900 ℃, a large amount of dicalcium silicate was generated, and damage cracks were more pronounced. The experimental results of this study are valuable of material design of fire resistance of LC3 concrete.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.4
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• pp.491-497
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• 2014

This study investigated the effects of alginate oligosaccharide on lipid metabolism in mice fed a high-cholesterol diet for 6 weeks. Male apoE mice were assigned to four groups: normal diet group (N), high-cholesterol diet group (HC), HC with 5% alginate oligosaccharide group (HC-AOL), and 10% alginate oligosaccharide group (HC-AOH). Epididymal adipose tissue and kidney adipose tissue weights were significantly reduced in the HC-AOH group by 131.4% and 148.4%, respectively, as compared to the HC group. Serum total cholesterol (TC), triglyceride (TG), and LDL-cholesterol levels were also significantly reduced in the HC-AOH group by 57.5%, 51.4%, and 82.9%, respectively, as compared to the HC group. Hepatic TC and TG levels in the HC-AOH group were significantly reduced by 72.3% and 33.5%, respectively, as compared to the HC group. These results indicate that alginate oligosaccharide might improve lipid metabolism and reduce fat accumulation.

• Nutrition Research and Practice
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• v.9 no.6
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• pp.619-627
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• 2015

BACKGROUND/OBJECTIVES: Colitis is a serious health problem, and chronic obesity is associated with the progression of colitis. The aim of this study was to determine the effects of natural raw meal (NRM) on high-fat diet (HFD, 45%) and dextran sulfate sodium (DSS, 2% w/v)-induced colitis in C57BL/6J mice. MATERIALS/METHODS: Body weight, colon length, and colon weight-to-length ratio, were measured directly. Serum levels of obesity-related biomarkers, triglyceride (TG), total cholesterol (TC), low density lipoprotein (LDL), high density lipoprotein (HDL), insulin, leptin, and adiponectin were determined using commercial kits. Serum levels of pro-inflammatory cytokines including tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), interleukin (IL)-$1{\beta}$, and IL-6 were detected using a commercial ELISA kit. Histological study was performed using a hematoxylin and eosin (H&E) staining assay. Colonic mRNA expressions of TNF-${\alpha}$, IL-$1{\beta}$, IL-6, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2) were determined by RT-PCR assay. RESULTS: Body weight and obesity-related biomarkers (TG, TC, LDL, HDL, insulin, leptin, and adiponectin) were regulated and obesity was prevented in NRM treated mice. NRM significantly suppressed colon shortening and reduced colon weight-to-length ratio in HFD+DSS induced colitis in C57BL/6J mice (P < 0.05). Histological observations suggested that NRM reduced edema, mucosal damage, and the loss of crypts induced by HFD and DSS. In addition, NRM decreased the serum levels of pro-inflammatory cytokines, TNF-${\alpha}$, IL-$1{\beta}$, and IL-6 and inhibited the mRNA expressions of these cytokines, and iNOS and COX-2 in colon mucosa (P < 0.05). CONCLUSION: The results suggest that NRM has an anti-inflammatory effect against HFD and DSS-induced colitis in mice, and that these effects are due to the amelioration of HFD and/or DSS-induced inflammatory reactions.

• Journal of Korean Medicine for Obesity Research
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• v.9 no.2
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• pp.33-45
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• 2009

Objectives This study was performed to evaluate the relation between hair tissue mineral elements(HTME) and Heart rate variability(HRV) of the metabolic syndrome(MS). Methods 89 persons(41-69 ages) who visited Oriental hospital for medical examination were divided MS group(n=22) and control group(n=67). HTME and HRV were compared, and were analyzed correlation with five contents of the MS. Results (1) In total subjects, waist circumference had a positive correlation with Pb. Blood pressure had a negative correlation with Mg. High density lipoprotein cholesterol(HDL-chol) had a negative correlation with Pb, Sb and K, while positive correlation with Ca/K. Triglyceride(TG) had a negative correlation with Mg and Na/K, while positive correlation with K and Ca/Mg. (2) In total subjects, TG and fasting blood sugar(FBS) had negative correlation with high frequency(HF), while positive correlation with low frequency/high frequency ratio(LF/HF). (3) In MS group, most of the level of toxic minerals were higher, and the level of major nutritional minerals were lower, but there were no statistical signficance. In two groups, there is no contrast between the correlations of the MS contents and HTME. (4) In MS group, HF was significantly lower and LF/HF was higher than normal group. LF/HF had a negative correlation with waist circumference in MS group, while positive correlation in normal group. (5) In total subjects, TP had a positive correlation with Mg. In two groups, there is no contrast between the correlations of the MS contents and HRV. However LF/HF had a positive correlation with Na in MS group, TP and LF had negative correlation with Ca, while RMSSD and HF had negative correlation with Cu in normal group. Conclusion These results may suggest that HTME and HRV are useful in diagnosing and preventing the metabolic syndrome.

• Journal of Korean Medicine Rehabilitation
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• v.24 no.2
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• pp.1-13
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• 2014

Objectives The purpose of this study was to investigate the effects of Cheunggihwadamhwan (CGHDH) extract on lowering lipid, antioxidation and production of proinflammatory cytokines in rats fed on high fat diet. Methods 40 Male Sprague-Dawley rats were fed on high fat diet for 8 weeks and 32 rats (above 400 g) were randomly divided into 4 groups (8 mice in each group) : control group, 100 mg/Kg CGHDH group, 200 mg/Kg CGHDH group, 300 mg/Kg CGHDH group. We fed a control group of rats a basal diet and administered normal saline(100 mg/kg, 1 time/1 day) for 4 weeks. And We fed each experimental group of rats basal diet and administered an extract of Cheunggihwadamhwan extracts (100 mg/kg, 200 mg/kg, 300 mg/kg, 1 time/1 day) for 4 weeks. At the end of the experiment, the rats were sacrificed to determine their chemical composition. We measured lipid in plasma and liver, concentration of proinflammatory cytokines, antioxidative activity and gene expression. The gene expression level was investigated by the way of reverse transcription-polymerase chain reaction (RT-PCR). Results 1. Concentration of plasma FFA, plasma TG, plasma total cholesterol and plasma LDL-cholesterol showed a significant decrement in Cheunggihwadamhwan groups. However, concentration of plasma HDL-cholesterol showed a significant increment in 200, 300 mg/kg Cheunggihwadamhwan groups. 2. Concentration of liver total cholesterol and liver TG showed a significant decrement in Cheunggihwadamhwan groups. 3. Concentration of plasma TBARS showed a significant decrement in all Cheunggihwadamhwan groups. Concentration of liver TBARS showed a significant decrement in 200, 300 mg/kg Cheunggihwadamhwan groups. Concentration of liver GSH-Px, SOD and CAT showed a tendency to decrease in all Cheunggihwadamhwan groups. 4. Concentration of plasma IL-$1{\beta}$, plasma IL-6, TNF-$\alpha$ and NO, showed a tendency to decrease in all Cheunggihwadamhwan groups. Concentration of plasma IL-10 showed a tendency to increase in all Cheunggihwadamhwan groups. 5. In the analysis of reverse transcription-polymerase chain reaction (RT-PCR), the gene expression of Apo-B and Apo-E in the Cheunggihwadamhwan groups showed a low expression than that of control group. The ratio of Apo-B expression per $\beta$-actin expression in the showed a significant decrement in all Cheunggihwadamhwan groups. The ratio of Apo-E expression per $\beta$-actin expression in the showed a significant decrement in 300 mg/kg Cheunggihwadamhwan groups. Conclusions According to this study, the extract of Cheunggihwadamhwan showed a positive effect of lowering lipid, antioxidation and a control of producing proinflammatory cytokines.

• Journal of the Microelectronics and Packaging Society
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• v.21 no.1
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• pp.31-39
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• 2014

For mobile application, semiconductor packages are increasingly moving toward high density, miniaturization, lighter and multi-functions. Typical wafer level packages (WLP) is fan-in design, it can not meet high I/O requirement. The fan-out wafer level packages (FOWLPs) with reconfiguration technology have recently emerged as a new WLP technology. In FOWLP, warpage is one of the most critical issues since the thickness of FOWLP is thinner than traditional IC package and warpage of WLP is much larger than the die level package. Warpage affects the throughput and yield of the next manufacturing process as well as wafer handling and fabrication processability. In this study, we investigated the characteristics of warpage and main parameters which affect the warpage deformation of FOWLP using the finite element numerical simulation. In order to minimize the warpage, the characteristics of warpage for various epoxy mold compounds (EMCs) and carrier materials are investigated, and DOE optimization is also performed. In particular, warpage after EMC molding and after carrier detachment process were analyzed respectively. The simulation results indicate that the most influential factor on warpage is CTE of EMC after molding process. EMC material of low CTE and high Tg (glass transition temperature) will reduce the warpage. For carrier material, Alloy42 shows the lowest warpage. Therefore, considering the cost, oxidation and thermal conductivity, Alloy42 or SUS304 is recommend for a carrier material.

• Applied Chemistry for Engineering
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• v.8 no.2
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• pp.267-275
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• 1997

$ZrO_2$ Powder was Prepared by sol-gel process and the adsorption characteristic of cobalt($Co^{2+}$) by $ZrO_2$ adsorbent in high-temperature water was investigated using batch adsorption experiment with a stirred autoclave. The prepared $ZrO_2$ was calcined at $600{\sim}1400^{\circ}C$ and analyzed by X-ray diffractometry, SEM, BET surface area, FT-IR and TG-DTA measurement. The tetragonal Phase of $ZrO_2$ is produced $480^{\circ}C$ from amorphous gel at temperature $480^{\circ}C$. Both tetragonal and monoclinic phase of $ZrO_2$ exist at temperature between $600^{\circ}C$ and $1000^{\circ}C$. At temperature $1200^{\circ}C$, tetragonal to monoclinic phase trasition is occurred. The $Co^{2+}$ adsorption capacity of $ZrO_2$ calcined at $600^{\circ}C$ for 4 hours is 0.16 meq $Co^{2+}/g$ adsorbent in the high temperature at $250^{\circ}C$. The adsorption of $Co^{2+}$ on the $ZrO_2$ adsorbent is irreversible endothermic in the temperature range ($125-175^{\circ}C$). The standard enthalpy change (${\Delta}H^{\circ}$) of $ZrO_2$ calcined at $600^{\circ}C$ for 4 hours is 18 kJ/gmol.